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GM alternator conversion

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V8Blazer

V8Blazer

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Just curious what is involved from those who have done it. GM alternators can be had for a song, and Ive read of it in the past. Fabricating brackets is easy enough, anyone have photos of their completed conversion?
 
I recently converted my old tractor to a GM alternator. That one had only one wire to it and that was the big lead from the battery. Everything is internal.It works great and is the simplest installation you could get.

I haven't done it to my MG because the original is still fixable.
Bob
 
Sweet. The way I figured, was that since it is all torn down right now for the head, why not do some reliability stuff while I'm there. GM alternator and a new water pump. Hopefully freeing up some ponies at the same time by getting rid of the direct drive fan for an electric, no more smog junk and the new aluminum head with light portwork and gasket matching. Mild cam and exhaust to follow soon.
 
Just a word to the wise on the GM alternator conversion: the GM Delco unit is BIG, large. It's a fair bit larger than the Lucas unit and tends not to look so great. I installed one on my GT6, it performs great, but . . .

There are alternatives to alternators (pun intended?). The Isuzu Trooper unit comes to mind, much smaller, good performance.

I hope this is helpful, good luck!
 
I recently converted my MGB to a Saturn 60 amp alternator. The results are great and the only complication was converting the drive pulley to one compatible with the MGB pulley stye since the Saturn uses serpentine type. The 60 amps handles the electric cooling fans very nicely. Older GM alternators did not have the capacity to drive the fan motors as well as the original Lucas.
 
But you can get an older GM style, most were 63 amp by the way, for 29.99 at the local parts store, which WILL drive electrics just fine. If you want you can get a 140 amp in Summit for 169, but that seems a bit overkill for these applications. Anyone have any close up pics of the actual mounting?? Thanks guys.
 
Why waste your time and money on a Delco? You have to make new mounts and modify the harness on your car. Use a Bosch alternator from a 1980 Ford Fiesta instead. It is a direct bolt on swap, uses the same plug without any harness mods and is smallet then the Delco. I have bought two of these on the internet for $59 and free shipping. Beats the heck out of having to build bracketry
 
2nd Gerry's comment. Not wanting to muck with new bracket, etc. I bought one from some folks in South Carolina who do their own remans. Actually since I could buy 2 for the price of one locally at NAPA, I did. Convert to 3 wire and straight bolt up. 55 amps. Possibly might need to grind a very small amount to get perfect line up but I didn't have to. Also...needed to grind/cut part of end off of bracket to get it to fit on the alternator so bracket won't hit fan blades on alt and buy a 1/2 inch longer belt so alternator will clear the motor mount. Still....pretty easy.
 
Re: And here's the source

Ok, so I'm ready to get rid of/fix my alternator. Now that it's dark when I go home hitting the brakes causes my car to stall (when i have the lights on), and the car stalls when i turn on my wipers. In both cases, my charge indicator goes bright red as the car is stalling. If i don't intervene by taking my foot off the brake and applying the gas it will stall 100% of the time. The PO had an electronic ignition installed with a IR distributor. So, I'm assuming the added power draw from the lights coupled with wiper usage/brake application is causing the electronic ignition to starve and resulting in the car stalling. So, i'm looking to do something about my alternator.

What's the common concensus here on the alternators? Go with the GM? or the Bosch?
 
Re: And here's the source

I have a bosch (Saturn 110amp) alternator that doesn't work but it would be great for a core if you want it. Pay shipping and it's yours. I woudl recomend the bosch because it uses the same brackets that you already have and it can reversed alot simpler.
 
Re: And here's the source

thanks for the offer adam, but after checking around on the prices of those 110Amp units I decided that those particular units are a little beyond my financial capabilities even with the core swap. I got one of the 55Amp fiesta bosch units instead, and just recieved it from FedEx lastnight.

But I still have a question or two before I jump head long into this project... Gerry mentions that it even uses the same plug and no wire harness mods are needed for this swap. So, being the person that hates to make assumptions that I am, I have to ask... Does that mean that all the wires hook up to the Bosch in the same order that they're hooked up to the Lucas unit? Or do I need to follow the diagrams that are on the website that Steve_S posted? Or am I just over thinking this (I've been accused of doing as much concerning various matters) and should just get in there and do it?
 
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